Improved power quality in distribution system with renewable energy sources integration

Abstract

Customers of electric utilities are increasingly concerned with meeting the growing energy demand. Petroleum derivatives account for 75% of global energy consumption, but issues like air pollution, global warming, and depleting petroleum supplies make sustainable energy sources a vital alternative. Distributed generation (DG) refers to renewable energy sources (RES) integrated at the distribution level, which can introduce challenges in power quality (PQ), voltage regulation, and system stability due to the intermittent nature of RES. Inverters, acting as active inductors, help mitigate harmonic currents in the system. This paper proposes a method where a shunt active filter reduces harmonic distortion in the distribution network using a control strategy based on SRF (Synchronous Reference Frame) computation. The method compensates for load current harmonics and imbalance, improving power quality at the point of common coupling (PCC) without additional power conditioning equipment. The system employs an inverter integrated with advanced control to function as both a power filter and a source of real power for the grid. The SRF technique helps detect and compensate for non-linear load currents and voltage imbalances. Simulation results using MATLAB/Simulink demonstrate the effectiveness of the proposed system across various non-linear load conditions. The PI regulator efficiently maintains the inverter's capacitance voltage, ensuring balanced grid-side flows. This method simplifies the implementation of power conditioning and enhances the system's performance at the PCC.